【作者】 徐娜；

【导师】 赵春晖；

【作者基本信息】 哈尔滨工程大学 ， 电磁场与微波技术， 2007， 硕士

【摘要】 近年来，移动通信业务发展迅速，作为发射和接收电磁波的重要射频前端器件——手机天线，正在朝着小型化、内置化、多频段、智能化方向发展。微带天线以其特有的体积小、重量轻、低剖面、可共形的特点，成为了手机内置天线的最佳选择。但同时微带天线自身增益低、带宽窄的缺陷在一定程度上限制了它的应用。本文首先介绍了微带天线的基本理论，对各种小型化、多频段和宽频带技术进行了归纳、分析与验证。接着重点研究了应用最为广泛的平面倒F天线(Planar Inverted-F Antennas，PIFA)的辐射原理和电特性，并结合多种小型化、多频段和宽频带设计方法提出了一种新型结构的手机终端三频PIFA。该天线结构紧凑、造型简单，可在GSM900MHz，DCS1800MHz和ISM2450MHz三个频段工作，满足了新一代无线通信系统对频段和带宽的要求。最后详细论述了圆极化微带天线的辐射原理及各种实现方法，在探讨了PIFA双极化(垂直极化、水平极化)工作的基础上，给出一种可实现圆极化辐射的PIFA结构。在分析、设计过程中，应用Ansoff公司的HFSS电磁仿真软件，对天线尺寸进行设计和优化，结合仿真结果讨论了主要参数的变化对于天线各项性能指标(包括谐振频率、频带宽度、方向图、阻抗圆图、3dB轴比带宽等)的影响。更多还原

【Abstract】 Mobile communication systems have experienced enormous growth in recent years. As the most important radio-frequency front device, handset antenna is developing into miniaturization, built-in, multi-band and intelligence. Microstrip antennas have many features like small size, light in weight, low profile and conformal, so they become the optimal choice for handset internal antennas. Unfortunately, some shortcomings of microstrip antennas such as low gain, small bandwidth, etc, make them unfit for practical application.First this thesis describes the basic theory of microstrip antennas, summarizes and analyzes the technology of miniaturization, multi-band and broadband. Then radiation principle and electrical performance of the fashionable planar inverted-F antennas (PIFA) is discussed and a novel handset terminal antenna PIFA is designed with many technologies of miniaturization, multi-band and broadband. The proposed antenna is compact and easy to build, and it also can operate in GSM900, DCS1800 and ISM2450 bands, which allows the design to be satisfied with wireless and portable communication systems. Last discusses the theory and realization method of circular polarization (CP) for microstrip antennas in details, and proposes a PIFA with CP radiation based on.research of dual- polarization(vertical and horizontal).The dimension of the presented antenna is designed and optimized with EM simulation software HFSS from Ansoft company. The influence of characteristic data as primary parameters modifying is discussed particularly(including resonant frequency, bandwidth, directivity diagram, impedance chart, 3dB axial ratio bandwidth, etc).更多还原